This invention relates to a multimedia terminal equipment and a digital signal processing method which can process broadcasting signals provided by various broadcasts such as, for example, a television broadcast in which a ground wave is used, a satellite broadcast in which a geostationary satellite is used or a cable television broadcast so that the broadcasting signals may be utilized.
In recent years, in addition to an analog television broadcast in which a ground wave is used, a digital television broadcast in which a geostationary satellite is used and a cable television broadcast which provides a television broadcasting program over a cable have become increasingly popular.
For example, in a digital television broadcast in which a geostationary satellite is used, a data compression technique of the MPEG system or the like is used to compress data to produce signals of a plurality of television broadcasting programs, and the signals thus produced are multiplexed on a single carrier so that they can be provided as a television broadcast. In other words, a digital television broadcast allows provision of a plurality of broadcasting programs by one channel. Further, also provision of contents information such as a web page produced in the HTML (Hyper Text Makeup Language) is made possible by a digital television broadcast.
Meanwhile, a cable television broadcasting makes it possible to provide a broadcasting signal stably to the user side because the broadcasting station side and the user side are interconnected over a cable. Also a so-called interactive television broadcast is being put into practical use wherein not only a television broadcast is provided from the broadcasting station side, but also a response from a user can be sent to the broadcasting station side over a cable making use of the advantage that the broadcasting side and the user side are interconnected by the cable.
By the way, in order to make use of a service whose provision has newly become possible by a digital television broadcast in which a geostationary satellite is used or a cable television broadcast described above, it is frequently demanded to receive and make use of the digital television broadcast or cable television broadcast in addition to a conventional analog television broadcast which is based on a ground wave.
However, as described above, for example, in a digital television broadcast in which a geostationary satellite is used, signals of a plurality of broadcasting programs are provided in a form wherein they are, for example, MPEG compressed and multiplexed on one carrier. Therefore, if it is tried to enjoy a digital television broadcast in which a geostationary satellite is used, such processes as to select a carrier on which an object broadcasting program is multiplexed, demodulate the carrier to obtain a transport stream, extract a signal of the object broadcasting program from the transport stream and decompress the extracted signal are required.
On the other hand, also in a cable television broadcast, such processes as to receive a digital broadcasting signal of compressed data supplied over a cable and decompress the received digital broadcasting signal are required.
Therefore, the user must prepare a reception apparatus corresponding to a broadcasting system of a television broadcast to be enjoyed. Accordingly, for example, if it is intended to receive, in addition to a conventional analog broadcast in which a ground wave is used, a digital television broadcast in which a geostationary satellite and a cable television broadcast, then another reception apparatus for the digital television broadcast and a further reception apparatus for the cable television broadcast, are required.
However, to prepare all of reception apparatus corresponding to television broadcasting systems to be enjoyed requires a high cost and imposes a heavy burden upon the user. Further, in this instance, the user must selectively use the plurality of reception apparatus in accordance with the broadcasting system of a television broadcasting program to be enjoyed, and this is complicated and cumbersome to the user.